1. Field of Invention
This invention relates, generally, to touch up kits for the repair of damaged paint. More particularly, it relates to a kit that reduces the level of skill required to perform a professional quality repair.
2. Description of Prior Art
Although every vehicle driven on the road has or will have paint chips, a survey of available paint repair products at auto parts stores, department stores, new car dealerships and similar businesses indicates that such businesses carry only a small, inadequate rack of touch-up lacquer based paints. Although hundreds of millions of products have been purchased over the years to repair paint chips, major manufacturers in this field have never introduced an effective and inexpensive repair kit for the consumer.
The need for prompt repair of chips and scratches in automotive paint is even more urgent today than it was in the past, in view of the use of thinner metal for automotive outer body panels and the need to preserve today's factory paint and rust-through warranties.
An effective paint chip repair kit would provide means for effective surface preparation and paint application; it would also include a universal touch-up paint. An even better cosmetic repair would require still further elements, such as special sandpaper and polish, to restore a smooth, flat, unbroken surface to the finish.
Proper surface preparation is a critical first step in any paint repair job, large or small; it is also the most neglected aspect in consumer paint chip repair. If surface rust, road film, tar, wax, silicone, moisture, salt and the like are not removed, the touch-up paint will separate from the surface and create a pocket that wicks in moisture and accelerates destruction of the steel panel and blistering of surrounding paint. Moreover, if the surrounding paint is not sufficiently "scuffed," the touch-up paint will not adhere at the edges of the repair, again creating a separation that traps moisture and accelerates deterioration of the paint and substrate.
The most common means of surface preparation for paint chips and scratches are chemical rust-converters, scraping, sanding, and glass fiber bristle brushes.
Chemical rust-converters use phosphoric acid-based compounds to chemically change iron oxide to a nonoxidant. 3M Corporation's RUST AVENGER (trademark) is a pen-shaped device that enables a user to apply such a compound to paint chips and scratches. Chemical rust converters are unable to remove road film, tar, wax, moisture and salt, or abrade the paint that surrounds the chip.
The automotive industry is now employing plastic and aluminum for many body panels. Corvette, Avanti, and Fiero cars have long had outer body panels made of plastic materials. More recently the Saturn, GM mini vans, and new Camaro/Firebirds use plastic extensively for their outer body panels. Aluminum is employed in various Cadillac fenders and hoods and is increasingly used in Ford Motor Company's models. Chemical rust converters are inappropriate for all these applications. It should be noted that chemical rust converters are also inappropriate for steel panels where the chip or scratch does not extend to the bare steel through the primer, E-coat, and galvanized layers.
A paint touch-up kit having a bottle and cap that includes a blade-like tool for rust removal is described in U.S. Pat. No. 4,522,523. However, surface preparation that includes scraping with such a tool has serious drawbacks. The tool may not necessarily abrade the surrounding paint, but a slip can easily cause more damage than the original chip. Scraper tools are also inadequate to remove all the road film, tar, wax, silicone, moisture and salt from the surface undergoing preparation because the tips of such tools are wide relative to the small recesses, low spots, rust pits and the like that require cleaning. Thus, such scraping instruments hit only the high spots of the surface being prepared.
Sanding presents problems similar to those of scraping. The backing that forms a part of standard sandpaper does not flex sufficiently to get into small recesses or into the corners of chips and scratches. Moreover, sandpaper unnecessarily removes ayers of paint contiguous to the chipped area. Feather edging, a phenomenon associated with sandpapering, is appropriate for blending the surfaces of large paint and body work repairs but it creates problems for chip and scratch repairs. If a smooth unbroken surface is to be restored to the paint finish, feather edging necessitates the filling of contiguous areas with touch-up paint in decreasing thickness as the touch-up paint approaches the edges of the sanded area. When the film thickness of the touch-up paint is reduced to 1 mil or less, cracking, separation and delamination become likely.
For most consumers, glass fiber bristle brushes provide the best surface preparation. Such brushes are so effective that they are also the tool of choice for many professionals. The diameter of each individual bristle is about two thousandths of an inch, enabling it to get into small recesses and rust pits. The fiberglass is sufficiently strong to brush away surface rust without abrading contiguous paint. Experiments have shown that with light pressure, the bristles are similar to 2000 grit sandpaper; with greater pressure, they sand like 400 grit paper. Such brushes also remove road film, tar, wax, silicone, moisture and salt from the surface while properly scuffing the edges of the chip or scratch as required to achieve long lasting adhesion by the touch-up paint. Such brushes work equally well with and without detrimental effect to aluminum and plastic substrates, primer, E-coat, or galvanized undercoats.
The glass fiber bristle brushes heretofore known, however, have certain shortcomings.
For example, Lowe, a German company, manufactures a brush having no moving parts. It includes a glass fiber cartridge that cannot be retracted or advanced without disassembling the holder; it also requires handling of the glass fiber cartridge. The design includes room in the body of the brush for the storage of extra cartridges, but some disassembly is required to gain access thereto. A user must grasp the fiberglass cartridge to advance the bristles as they wear. Perhaps more importantly, retraction of the bristles also requires handling of the cartridge. This is problematic because the fiberglass strands break off the sides or end of the cartridge and become temporarily embedded in the skin. Thus, the cartridge should be retracted when the tool is stored, but such retraction requires disassembly of the tool as aforesaid; accordingly, the average consumer leaves the bristles unretracted. Thus, when the brush is later retrieved from a drawer or other storage location, fiberglass bits get into the skin of the person retrieving the tool.
Another product in this field, manufactured for Northstar, is known as the RUST SURGEON (trademark). Advantageously, the cartridge can be extended or retracted by turning the cap, but the device includes no storage area for replacement cartridges. The cartridges are shipped loosely in the package, and loose fiberglass penetrates the skin of the person who opens the package; it also spreads all over the table or other work place.
The lack of any storage means for the cartridges within the tool also makes it easy for the cartridges to get lost or misplaced. Safety considerations are also a problem because typically the loose cartridges are placed in a desk, kitchen drawer, or tool box. Without proper storage, the fiberglass stands break off and pierce the hands or arms of people reaching into such drawers or tool boxes. Moreover, the design greatly increases the risk that the cartridges might be handled by children.
Although fiberglass has been used in homes and industry for decades, ranging from structural materials and tools to insulation, and although common sense should tell people to keep tools containing fiberglass out of the reach of children, the increasing litigious nature of society makes reduction of product liability exposure of paramount importance to manufacturers and distributors. It is not sufficient to have warnings on packaging alone because the original packaging may not be seen by secondary users. It would therefore be advantageous to have adequate space on the tool itself for a permanently attached, sufficiently large warning label, but earlier tools in this field lack said sufficient space or are otherwise not amenable to the placing of warning signs thereon. For example, the Lowe device has a grooved outer surface that is unsuitable as a mounting location for a warning label, and the Northstar device has a label-defeating narrow, multifaceted outer surface. Moreover, the Lowe device requires frequent disassembly, thereby rendering impractical the placing of a permanent warning label thereon.
The earlier devices also have several structural disadvantages. For example, the Northstar design uses a coiled wire as a spiral thread so that rotation of the cap forces a pawl down the wire. The wire is therefore the only axial support for the cartridge; it can be pushed back into the tool during use.
The Northstar design also includes separate metal components; accordingly, a single mold cannot be used to make all of said components. The design also employs internal threads the fabrication of which requires very expensive and sophisticated molds. Moreover, to produce an aesthetically pleasing multicolor tool, the parts must be made with different colors of plastic; this requires a split mold or two separate runs using an unsplit mold.
Conventional paint application tools include touch-up paint bottles that include built-in brushes, specially designed pin stripe style brushes, and small spray equipment; each of these has significant drawbacks.
Some touch-up paint bottles have a brush attached to the bottle cap, but the brushes are far too large for the repair of most paint chips, i.e., they are too wide and they deliver too much paint. When wetted they are typically 0.140 inch in width at the bristle end, whereas a typical paint chip is only about 0.090 inch in diameter and 4 mils in depth, thus requiring only about 0.1 grams of paint. A typical touch-up paint bottle brush delivers as much as 0.5 grams in the first drop transferred. For this reason, professional automotive paint refinishers generally prefer to use paper matches to apply touch-up paint.
Specially designed brushes are not usually sold in most auto parts stores, department stores or car dealerships. In addition, they are more expensive (generally $15 and up) than most consumers would want to pay for a one-time use. Their effective use also generally requires experimentation and practice. Moreover, they have to be cleaned after each use.
Spray equipment has the multiple drawbacks of initial cost, difficulty of use, the need for paint mixing, the requirement of masking surrounding areas, and the application of paint where it is neither wanted nor required. A paint repair kit sold by B&M Automotive costs $40 to $50 and uses a small sprayer connected by a long hose to a vehicle's tire valve.
After surface preparation and application of touch-up paint to a paint chip, the finish is still not cosmetically restored because the touch-up paint forms a raised surface that must be brought down to a level flush with the original paint.
U.S. Pat. Nos. 5,082,692 and 5,077,086 disclose methods wherein a soft, flexible sheet material applies specially blended solvents to dissolve and wipe off excess touch up paint while the paint is partially set. Several significant problems are associated with such process. As the repaired painted surface is wiped with solvent, paint must not be removed from the chip or scratch but excess touch-up paint must be completely removed. Flexible material naturally pushes down into repaired chips or scratches which are filled with partially set touch-up paint. Furthermore, solvent naturally flows into such low lying areas. Solvent is not an exact or efficient means of creating a smooth and flat surface to a partially set painted area, particularly when the solvent is applied by wiping the surface with a flexible material. Resulting edges, waviness and wipe marks are clearly visible to the naked eye. Moreover, partially set touch-up paint shrinks as solvents therein evaporate. As a result, a recess or depression develops in the touch-up area after a few days. Such depressions or other surface imperfections as small as a few ten thousandths of an inch are visually discernible on a good automotive finish.
The Final Finish System (trademark) marketed by Eastwood uses small circular pieces of sand paper which have scalloped edges. Because they are so small, the paper requires an adhesive system for mounting to a custom sanding spool which further increases cost.
Additionally, the circular design, along with the scalloped edges, creates a considerable amount of waste because these pieces are die cut from standard sheets of sand paper.
Additionally, the circular design of the pre-cut sandpaper is not well suited to paint chip repairs. As the pieces are rotated, very little sanding occurs at the center of the disc where the paint chip is located and therefore where the most paint needs to be removed. During each revolution, the largest relative surface motion is at the edges because of their distance from the axis of rotation. The result is that the most sanding occurs where it is least wanted, and the least sanding occurs at the one place where it is most needed.
The Final Finish System has no means to prepare the surface, and it lacks paint applicators and a universal touch up paint.
A good paint blemish repair job must end with application of a suitable polish. However, finding a polish that can be applied by hand and that includes a proper abrasive is not an easy task for professional or consumer. There is no rating system on polishes, compounds and paint "cleaners" to grade their abrasive level, and the product description on the labels is generally not helpful in making this type of comparison. A consumer could spend hundreds of dollars on retail or trade polishes before finding one satisfactory for a particular grade of ultrafine paper.